Reciprocating engine



J. McKECHNlE.

RECIPROCATING ENGINE. APPLICATION FILED OCT. 6, 1920.

1 A l 9, 1 :5 9 9 Patented J 11110 13, 1922.

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64M. jh /(w M, saw; mm 6M J. MCKECHNIE.

RECIPROCATINGENGINE.

APPLICATION FILED OCT. 6. I920- 1,419, 159., PatentedJune 13, 1922,

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J MCKECHNIE.

RECIPROCATING ENGINE.

APPLICATION FILED OCT. 6. 1920.

Patented June 13, 1922.

4 SHEETS-SHEET 3- J. McKEHNlE.

RECIPROCATING ENGINE;

APPLICATION FILED OCT. 6, 1920 1,419 159;, Patented June 13, 1922,

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Q Q I 0 0 L w 1 W1 engines, of the type ing space 'ing between mains nexnonmn'or BARROW-IN-FURNESS, ENGLAND, ASSIGNQR To V103 mmrrnn, or WESTMINSTER, LONDON, ENGLAND.

REOIPROCATING ENGINE.

Specification of Letters Patent. Patgnt d J 13 1322 Application filed October 6, 1920. Serial No. 415,165.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L, 1318.)

T 0 all whom it may concern Be it known that 1, JAMES MoKEoHNIE, a subject of the King of Great Bl'ltflln, residing at Naval Construction Works, Barrow-in-Furness, in the county of Lancaster, En land, have invented certain new and use ul Improvements in or Relating to Reciprocating Engines (for winch I have filed an application in Great Britain, No. 23,028, Sept. 18, 1919, Patent No. 165,861), of which the following is a specification.

This inventionrelates to reciprocating engines, such as internal combustion or steam employing opposed pistons in a common cylinder and connected to a common crank shaft.

The chief object of theinvention 1s to reduce to a minimum the unbalanced stresses due to the movements of the large masses of the various engine members, more especially the secondary or lateral stresses which in engines of this class as hitherto constructed are of a substantial nature,-although the longitudinal stresses are largely balanced by the opposing action of the pistons.

According to this invention each one of a pair of cylinders carries a pair of oppositely acting pistons with a common working connected to the ends of a' pair of rocking levers placed at opposite ends of the cylinders and connected to each other atone end through a link, a connecting rod attached to the link onto one of the levers driving the crank of the engine shaft. The end of the connecting rod may be guided by a slide workin in a. guide in the engine cast e two cylinders or, if the links connecting the rod to the rocking levers are constructed as a single member 'jextending from one lever to the other, this member may. withstand the comparatively small side stresses, whichare then borne by the trunnions of the rocking levers.

' The links between the levers andthe connecting rod are subjected both to tension "and compression, but compression may be avoided by'connectingthe opposite ends of the rocking levers by a tension rod independent of the connecting rod. The working strokes of the two cylinders alternate, the

pistons in one cylinder performing their inbetween them, the said pistons beward stroke while the other pistons are on their outward stroke.

In order that the said invention may be clearly understood and readily carried into effect we will now describe the same more fully with reference to the accompanying drawings, in which 1-- Figure 1 is a sectional elevation ofa construction of internal combustion engine embogying this invention,

igure 1 is a sectional elevation at right. I

pivot pins C". E is the crank shaft. F is the connecting rod driving the shaft E. The

rocking; levers and links are duplicated for purposes ofsymmetry and balance.

Referring to the arrangement shown in Figs. 1, 1 and 1", the cylinders A are shown symmetrically placed on each side of the crank shaft E,'to the crank pin e of which is secured the outer end of the connecting rod F, the upper or inner end 0f which is pro-r vided with the crosshead f on the cross pin d of the link D. The crosshead is shown with the slipper bars f sliding between guides g on the engine casing G, so that any side stresses which may arise are taken by the guides and the engine casing on the frame G, which is mounted on the base G, the latter carrying the bearings g for the shaft E.

The lower lever C is pivotally mounted on trunnions 0 carried by the frame G and diagrammatic elevathe upper lever C is mounted on trunnions 0 carried by the bracket or upper frame G which is connected to the base G by the tie rods 9 The upper arm of the link D is shown as lar er than the lower arm and the pistons B," 1 are shown unsymmetrically placed in their cylinders A so that the exhaust ports a leading to the exhaust outlet 7 till a at the upper end of the cylinders are uncovered before the inlet ports 0, leading from the air inlet a* at the lower end of the cylinder. The levers C, C and link D are each duplicated, as already mentioned, and as shown in Figs. 1 and 1", for purposes of symmetry and balance, the connecting rod F being single and therefore placed centrally of the engine between the two pairs of lever and link members.

The engine operates on ordinary two stroke lines, but the flow of gases is, as is in the known opposed piston type of engine, always in the same direction, the air entering at one end of the piston and the gases ex austing at the other. The use of a connecting rod for driving the shaft enables a compact form of engine to be designed, the cylinders close together and the crank shaft in any position that may be desirable. The secondary stresses due to unbalanced inertia forces are reduced to a minimum by the combination of cross connected rocking levers'with a connecting rod drive for the shaft. The inner end of the connecting rod moves in a practically straight line parallel to the cylinders and any side stresses thatmay occur due to the angle of the connecting rod at half way positlons can be taken by the guides g and therefore by the main frame of the engine.

'In the modification shown diagrammatically in Figures 2 and 3 the rocking levers C, C at each end of the cylinders A are double (see Figure 3) and a pair of links D is provided, one at each side of the cylinders, the cross pin d connecting the two links at the middle and providing for the attachment of two connecting rods F driving a pair of cranks e on the crank shaft E. The cross pin and the ends of the connecting rods may be attachedto one side of the link as shown in Figure 2, the crank shaft E being correspondingly displaced from the centre line of the engine.

In the modification shown in Figure 4 twin crank shafts E are employed and the two connectin rods F connect to the opposite ends of t e lower rocking lever C instead'of directly to the link D. Or as shown in Figure 5 the connecting rods F may be attached to the opposite ends of a rocking lever 0 carried on the shaft 0 of the upper piston driven rocking lever C, the connecting rod lever C extending beyond the cylinders A so as to allow the connecting rods F to clear the latter. The twin shafts E in this case are placed outside the line of the the opposite rocking lever C having a corresponding arm or lug c for attachment of the other end of the link.

We may also, as shown in Figures 7 and i cooled pistons, but with this arrangement cylinders of sufficiently small diameter can be utilized to develop the same horse power and render water cooling of their plstons' unnecessary, and for the powers above this oil cooling might be adopted and only water cooling would be required for larger cylinders of, say, over 12" diameter for twostroke engines, or over 17 diameter for four-stroke engines.

What I claim and ters Patent of the United States is:--

1. In a reciprocating engine, a pair, of cylinders, a pair of oppositely acting pistons in each cylinder, a pair of rocking levers one at each end of the cylinders, driving connections from the said rocking levers to the four pistons, a rigid link connecting diagonally the two IOCkll'lg'lQVGlS, a crank shaft and a connecting rod interposed between'the said shaft and the rocking leverlink system and driving the shaft from the said system.

2. In a reciprocating engine, a pair of cylinders, a pair of oppositel acting pisdesire to secure by Lettons in each cylinder, a pair 0 rockin levers one at each end of the cylinders, drlving connections from the said rocking levers to the four pistons, a rigid link connecting diagonally the two rocking levers, a guide maintaining the path of the middle of the link substantially parallelwith the axes of the cylinders, a crank shaft and a' connect-- ing rod interposed between the said shaft and the rockin lever-link s stem and driving the shaft rom the sai system.

3. In a reciprocating engine, a pair of cylinders, a pair of'oppositely acting istons in each cylinder, a pair of rocking evers one at each end of the cylinders, driving connections from the said rocking levers to the four pistons, a rigid link connecting diagonally the two rocking levers, a crank shaft, and a connecting rod driving the crank shaft which rod is pivotally connected at its other end to the middle of the diagonal link whereby the pivoted end of the rod moves in a substantially straight path parallel to the axes of the cylinder.

release 4. In a reciprocating engine, a pair of cylinders, a pair of oppositely acting pistons in each cylinder, a pair of rocking lever members on a fixed fulcrum at one end or the cylinders, piston connecting rods from the pair of pistons at the same end to the opposite ends of the said lever members, a second pair of rocking lever members at the opposite end of the cylinders, fulcrum pins for the said members, piston connecting rods from the second pair of pistons to the ends of the second pair of lever members, a air of connecting links connected diagonal to opposite ends or the two pairs of rocking lever members, a crank shaft and a central connecting rod driving the said crank shaft, which rod is connected to the middle of the pair of diagonal links and lies between the second pair of rod :i-nglever members.

5. In a reciprocating engine, a pair of parallel cylinders, a pair of oppositely acting pistons in each cylinder, interconnecting members between the pistons of both cylin ders including a rigid diagonal link between the pistons at opposite ends of the two cylinders, a crank shaft and a connecting rod connected to about the middle of the said diagonal link and driving the said crank shaft.

In testimony whereof TL afi ix In signature JAMES Mel CHNIE. 

